Nissan Frontier. Manual - part 868

HAC-26

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

AIR MIX DOOR MOTOR

Air Mix Door Control Specification

COMPONENT DESCRIPTION

Air Mix Door Motors

The driver (1) and passenger (2) air mix door motors are attached to

the front heater & cooling unit assembly. These motors rotate so that

the air mix door is opened or closed to a position set by the front air

control. Motor rotation is then conveyed through a shaft and the air

mix door position is then fed back to the front air control by the PBR

built into the air mix door motors.

Air Mix Door Motor (Driver) Component Function Check

INFOID:0000000009478278

INSPECTION FLOW

1.

CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - TEMPERATURE INCREASE

1. Turn the temperature control dial (driver) clockwise until 32

°C (90°F) is displayed.

2. Check for hot air at discharge air outlets.

>> GO TO 2.

2.

CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - TEMPERATURE DECREASE

1. Turn the temperature control dial (driver) counterclockwise until 18

°C (60°F) is displayed.

2. Check for cold air at discharge air outlets.
Can a symptom be duplicated?

YES

>> Inspection End.

NO

>> Go to diagnosis procedure. Refer to 

HAC-26, "Air Mix Door Motor (Driver) Diagnosis Procedure"

.

Air Mix Door Motor (Driver) Diagnosis Procedure

INFOID:0000000009478279

Regarding Wiring Diagram information, refer to 

HAC-63, "Wiring Diagram - Automatic Air Conditioner"

.

SYMPTOM:

• Discharge air temperature does not change.

• Air mix door motor does not operate.

1.

CHECK AIR MIX DOOR MOTOR (DRIVER) POSITION BALANCED RESISTOR (PBR) FEEDBACK VOLT-

AGE
1. Turn ignition switch ON.

WJIA0435E

ALIIA0756ZZ

AIR MIX DOOR MOTOR

HAC-27

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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HAC

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2. Using CONSULT, check "DVR MIX FDBCK" in "DATA MONITOR" mode in "HVAC". Refer to 

HAC-17,

"CONSULT Function (HVAC)"

.

3. Observe "DVR MIX FDBACK" voltage while rotating temperature control dial (driver) between 32

°C (90°F)

and 18

°C (60°F).

Is the inspection result normal?

YES

>> • Air mix door motor (driver) is OK.

• Inspect air mix door (driver) for mechanical failure and repair if necessary. If air mix door (driver)

is OK, refer to 

HAC-73, "Component Function Check"

 for insufficient cooling or 

HAC-81, "Com-

ponent Function Check"

 for insufficient heating.

NO

>> GO TO 2.

2.

CHECK AIR MIX DOOR MOTOR (DRIVER) CIRCUITS FOR OPEN AND SHORT TO GROUND 

1. Turn ignition switch OFF.

2. Disconnect the front air control harness connector M52 and the air mix door motor (driver) harness con-

nector M148.

3. Check continuity between front air control harness connector M52 terminals 17, 18 and the air mix door

motor (driver) harness connector M148 terminals 6, 5.

4. Check continuity between front air control harness connector

M52 terminals 17, 18 and ground.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair or replace harness as necessary.

3.

CHECK FRONT AIR CONTROL FOR AIR MIX DOOR MOTOR (DRIVER) POWER AND GROUND 

1. Reconnect front air control harness connector.

2. Turn ignition switch ON.

3. Rotate temperature control dial (driver) to 32

°C (90°F).

4. Check voltage between front air control harness connector M52

terminal 17 and terminal 18 while rotating temperature control

dial (driver) to 18

°C (60°F) and back to 32°C (90°F).

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Replace front air control. Refer to 

VTL-7, "Removal and Installation"

.

Monitor Item

Condition

Results

DVR MIX FDBCK

Rotate temperature control dial (driver) be-

tween 32

°C (90°F) and 18°C (60°F)

Voltage varies with dial rotation between 0.2 and 4.8 

volts.

Connector

Terminal

Connector

Terminal

Continuity

M52

17

M148

6

Yes

18

5

Connector

Terminal

—

Continuity

M52

17

Ground

No

18

AWIIA0374ZZ

Connector

Terminals

Condition Voltage 

(Approx.)

(+) (-)

M52

17

18

While rotating temperature control 

dial (driver) from 32

°C (90°F) to 18°C 

(60

°F)

Battery voltage

18

17

While rotating temperature control 

dial (driver) from 18

°C (60°F) to 32°C 

(90

°F)

Battery voltage

AWIIA0373ZZ

HAC-28

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

AIR MIX DOOR MOTOR

4.

CHECK AIR MIX DOOR MOTOR (DRIVER) PBR CIRCUITS FOR OPEN AND SHORT TO GROUND 

1. Turn ignition switch OFF.

2. Disconnect the front air control harness connectors.

3. Check continuity between front air control harness connector M52 terminal 3, connector M56 terminal 28

and air mix door motor (driver) harness connector M148 terminals 3, 1.

4. Check continuity between front air control harness connector M52 terminal 3, M56 terminal 28 and

ground.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair or replace harness as necessary.

5.

CHECK PBR FEEDBACK SIGNAL CIRCUIT FOR OPEN AND SHORT TO GROUND 

1. Check continuity between front air control harness connector M52 terminal 6 and air mix door motor

(driver) harness connector M148 terminal 2.

2. Check continuity between front air control harness connector

M52 terminal 6 and ground.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair or replace harness as necessary.

6.

CHECK FRONT AIR CONTROL FOR 5 VOLT REFERENCE (VREF), VREF RETURN, AND FEEDBACK

SIGNAL 
1. Reconnect front air control harness connectors.

2. Turn ignition switch ON.

3. Check voltage between front air control harness connector M52

(B) terminal 3, and M56 (A) terminal 28.

Connector

Terminal

Connector

Terminal

Continuity

M52

3

M148

3

Yes

M56

28

1

Connector

Terminal

—

Continuity

M52

3

Ground

No

M56

28

Connector

Terminal

Connector

Terminal

Continuity

M52

6

M148

2

Yes

Connector

Terminal

—

Continuity

M52

6

Ground

No

AWIIA0383ZZ

A

B

Connector

Terminals

Connector

Terminals

Voltage (Approx.)

(+)

(-) 

M56

28

M52

3

5 Volts

AWIIA0813ZZ

AIR MIX DOOR MOTOR

HAC-29

< DTC/CIRCUIT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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4. Check voltage between front air control harness connector M52

terminal 6 and ground.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Replace front air control. Refer to 

VTL-7, "Removal and

Installation"

.

7.

CHECK FRONT AIR CONTROL FOR FEEDBACK SIGNAL 

1. Reconnect the air mix door motor (driver) harness connector

M148.

2. Check voltage between front air control harness connector M52

terminal 6 and ground.

Is the inspection result normal?

YES

>> Inspect air mix door (driver) for binding or mechanical

failure. If air mix door (driver) moves freely, replace front

air control. Refer to 

VTL-7, "Removal and Installation"

.

NO

>> Replace air mix door motor (driver). Refer to 

VTL-23, "Removal and Installation"

.

Air Mix Door Motor (Passenger) Component Function Check

INFOID:0000000009478280

INSPECTION FLOW

1.

CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - TEMPERATURE INCREASE

1. Turn the temperature control dial (passenger) clockwise until 32

°C (90°F) is displayed.

2. Check for hot air at discharge air outlets.

>> GO TO 2.

2.

CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - TEMPERATURE DECREASE

1. Turn the temperature control dial (passenger) counterclockwise until 18

°C (60°F) is displayed.

2. Check for cold air at discharge air outlets.
Can a symptom be duplicated?

YES

>> Inspection End.

NO

>> Go to diagnosis procedure. Refer to 

HAC-29, "Air Mix Door Motor (Passenger) Diagnosis Proce-

dure"

.

Air Mix Door Motor (Passenger) Diagnosis Procedure

INFOID:0000000009478281

Regarding Wiring Diagram information, refer to 

HAC-63, "Wiring Diagram - Automatic Air Conditioner"

.

SYMPTOM:

• Discharge air temperature does not change.

• Air mix door motor does not operate.

DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR (PASSENGER)

1.

CHECK AIR MIX DOOR MOTOR (PASSENGER) POSITION BALANCED RESISTOR (PBR) FEEDBACK

VOLTAGE

1. Turn ignition switch ON.

Connector

Terminal

—

Voltage (Approx.)

M52

6

Ground

0 Volts

AWIIA0382ZZ

Connector

Terminal

—

Voltage (Approx.)

M52

6

Ground

0.2 to 4.8 Volts

AWIIA0382ZZ